-
1 Stumpf, Johann
SUBJECT AREA: Steam and internal combustion engines[br]fl. c. 1900 Germany[br]German inventor of a successful design of uniflow steam engine.[br]In 1869 Stumpf was commissioned by the Pope Manufacturing Company of Hertford, Connecticut, to set up two triple-expansion, vertical, Corliss pumping engines. He tried to simplify this complicated system and started research with the internal combustion engine and the steam turbine particularly as his models. The construction of steam turbines in several stages where the steam passed through in a unidirectional flow was being pursued at that time, and Stumpf wondered whether it would be possible to raise the efficiency of a reciprocating steam engine to the same thermal level as the turbine by the use of the uniflow principle.Stumpf began to investigate these principles without studying the work of earlier pioneers like L.J. Todd, which he later thought would have led him astray. It was not until 1908, when he was Professor at the Institute of Technology in Berlin- Charlottenburg, that he patented his successful "una-flow" steam engine. In that year he took out six British patents for improvements in details on his original one Stumpf fully realized the thermal advantages of compressing the residual steam and was able to evolve systems of coping with excessive compression when starting. He also placed steam-jackets around the ends of the cylinder. Stumpf's first engine was built in 1908 by the Erste B runner Maschinenfabrik-Gesellschaft, and licences were taken out by many other manufacturers, including those in Britain and the USA. His engine was developed into the most economical type of reciprocating steam engine.[br]Bibliography1912, The Una-Flow Steam Engine, Munich: R. Oldenbourg (his own account of the una-flow engine).Further ReadingH.W.Dickinson, 1938, A Short History of the Steam Engine, Cambridge University Press; R.L.Hills, 1989, Power from Steam. A History of the Stationary Steam Engine, Cambridge University Press (both discuss Stumpf's engine).H.J.Braun, "The National Association of German-American Technologists and technology transfer between Germany and the United States, 1844–1930", History of Technology 8 (provides details of Stumpf's earlier work).RLH -
2 Todd, Leonard Jennett
SUBJECT AREA: Steam and internal combustion engines[br]fl. 1885 London, England[br]English (?) patentee of steam engines incorporating the uniflow principle.[br]In a uniflow system, the steam enters a steam engine cylinder at one end, pushes the pistons along, and exhausts through a ring of ports at the centre of the cylinder that are uncovered by movement of the piston. The piston is returned by steam then entering the other end of the cylinder, moving the piston arrangement back, and again making its exit through the central ports. This gave the thermodynamic advantage of the cylinder ends remaining hot and the centre colder with reheating the ends of the cylinder through compression of the residual steam. The principle was first patented by Jacob Perkins in England in 1827 and was tried in America in 1856.Little is known about Todd. The addresses given in his patent specifications show that he was living first at South Hornsey and then Stoke Newington, both in Middlesex (now in London). No obituary notices have been traced. He took out a patent in 1885 for a "terminal exhaust engine" and followed this with two more in 1886 and 1887. His aim was to "produce a double acting steam engine which shall work more efficiently, which shall produce and maintain within itself an improved gradation of temperature extending from each of its two Hot Inlets to its common central Cold Outlet". His later patents show the problems he faced with finding suitable valve gears and the compression developing during the return stroke of the piston. It was this last problem, particularly when starting a condensing engine, that probably defeated him through excessive compression pressures. There is some evidence that he hoped to apply his engines to railway locomotives.[br]Bibliography1885, British patent no. 7,301 (terminal exhaust engine). 1886, British patent no. 2,132.1887, British patent no. 6,666.Further ReadingR.L.Hills, 1989, Power from Steam. A History of the Stationary Steam Engine, Cambridge University Press (provides the fullest discussion of his patents). H.W.Dickinson, 1938, A Short History of the Steam Engine, Cambridge University Press.J.Stumpf, 1912, The Una-Flow Steam Engine, Munich: R.Oldenbourg.RLH
См. также в других словарях:
List of rail accidents (1950–1999) — List of rail accidents from 1950 to 1999.For historic accidents before 1950, see List of pre 1950 rail accidents .For accidents from 2000 to the present, see List of rail accidents . notoc 1950s 1950* February 17 1950 ndash; Rockville Centre, New … Wikipedia
literature — /lit euhr euh cheuhr, choor , li treuh /, n. 1. writings in which expression and form, in connection with ideas of permanent and universal interest, are characteristic or essential features, as poetry, novels, history, biography, and essays. 2.… … Universalium
performing arts — arts or skills that require public performance, as acting, singing, or dancing. [1945 50] * * * ▪ 2009 Introduction Music Classical. The last vestiges of the Cold War seemed to thaw for a moment on Feb. 26, 2008, when the unfamiliar strains … Universalium
Italy — /it l ee/, n. a republic in S Europe, comprising a peninsula S of the Alps, and Sicily, Sardinia, Elba, and other smaller islands: a kingdom 1870 1946. 57,534,088; 116,294 sq. mi. (301,200 sq. km). Cap.: Rome. Italian, Italia. * * * Italy… … Universalium
Rockdelux — Logo de Rockdelux. Rockdelux est une revue musicale espagnole, spécialisée dans l étude des nouvelles tendances du pop rock alternatif et indépendant et de la musique électronique. Sommaire … Wikipédia en Français
